Great all-around car, exceptionally well-executed and excels at what it was designed to do -- turn heads! Love the power even with the auto trans, especially the down-low torque, and all the electronic goodies (Dynamic audio, sat radio, iPod). And oh, those Volvo seats! Incredibly comfortable on my 1-hr commute. My wife and I both get lots of compliments on the car's appearance, especially the all-glass hatch. I hate driving cars that everyone else has, and to date I've only seen two other C30s on the road. Huge cache factor. Respectable gas mileage (23 mpg avg on a mix of city/hwy driving). And no need for premium! Get the R-design package, it really makes the car's appearance pop.
Seats, iPod, sat radio, the all-glass hatch, and the dual chrome exhaust. Did I mention the seats?
Better fuel economy would be great of course. Everything else rocks!